Photographic color picture



Patented Aug. 11, 1942 2,293,004 rno'roomrmc COLOR. PICTURE HermannLohaus, Dessau, Germany, assignor, by mesne assignments, to GeneralAniline & Film Corporation, New York, N. Y., a corporation of DelawareNo Drawing. Application April 1, 1939, Serial No. 265,601. In GermanyApril 7, 1938 21 Claims.

My present invention relates to the manufacture of photographic colorpictures.

It is known to produce photographic color pictures with the aid of colordevelopment by using in the developer or in the photographic layer adyestuff former which during the development is oxidized together withthe developing substance at the places containing the silver image toproduce the dyestuif. As dyestuff formers for this color developmentthere have been proposed phenols, naphthols, aniline, naphthylamine,aminonaphthols and compounds having a reactive methylene group.

One object of my invention is to provide as the dyestuff former a simpleor substituted hydroxypyridine.

Another object of this invention is to provide as the dyestufi former acompound with a con- 4-methyl-6-hydroxy-2-pyridone. The silver halideemulsion having the dyestuil former fast to diffusion may be made into aphotographic layer in the known manner and there may be one or severallayers on one or both sides of a support superimposed on each other. Thelayers may be used for taking black and white pictures or colorpictures. For the purpose of color photography the emulsion layers arepreferably sensitized for different regions of the spectrum. If desiredseveral dyestuff formers may be contained in one layer and these may beso selected that on development a neutral grey picture is prodensedpyridine ring system having in the pyridine nucleus one or severalhydroxy groups.

Further objects of the invention will appear more in detail hereinafter.

The dyestuff former used according to the invention may be substitutedin the pyridine ring or in the condensed ring or rings in any desiredmanner. Examples of compounds suitable for the invention are3-hydroxypyridine, 2.6-dihydroxypyridine, 1-phenyl-6-hydroxy-2-pyridine,4-hydroxyisoquinoline, 1-(4-carbe thoxy-phenyl)-4-methyl-6-hydroxy-2-pyridone.

These dyestuff formers may be added either to a the developer or to theemulsion. With color developers, for example para-phenylenediamine or aderivative thereof blue or blue-violet dyestufi images are obtained.

When the dyestuii' formers are added to photographic layers it isrecommended that they should be made fast to diffusion in respect to thebinding agent of the layer by the introduction of special groups. Asgroups of. this kind there may be used those named in the British patentspecification No. 488,048 and in the U. S. Patents 2,178,612, 2,179,238,2,186,849, 2,186,850, 2,179,244, 2,186,732, 2,186,733, 2,156,821,2,186,851, 2,186,735, 2,186,734, 2,186,719, 2,186,852, 2,154,918,2,186,736 and 2,200,306. The group which renders the dyestufi formerfast to difiusion may be introduced into its molecule in a manner initdroxy-2-pyridone, 1- (4'-benzoylamin0diphenyl) duced.

The emulsion layers may also be made in other manner, for exampledifferently sensitized emulsions with different dyestuif formers may bedistributed in the form of small particles on a support.

The color picture may be produced in various ways for example in themanner described in any one of the U. S. Patents 2,179,228, 2,179,238,2,186,849, 2,178,612 and 2,186,730. In the exposed emulsion layers thepictures may be developed by simple color development or by reversaldevelopment, as described in U. S. Patents 2,229,137 and 2,179,234.

In the production of black and white pictures by this invention thesilver may be removed from the silver halide emulsion layer or thesilver may be allowed to remain in the layer together with the dyestuifpicture.

The following examples illustrate the invention:

Example 1.'-To 1 kilo of a silver halide emulsion there are added 5grams of 3-hydroxypyridine and the emulsion is cast to form a layer.After exposure development with para-dimethylaminoaniline produces abluedyestuil image.

Example 2.--To 1 kilo of a silver halide emul-- sion there are added 5grams of 2.6-dihydroxypyridine. This emulsion is cast to form a layer.After exposure development with para-dimethylaminoaniline produces ablue dyestuif image.

Example 3.-To 1 kilo of silver halide emulsion there are added 5 gramsof l-phenyl-4-methyl-6-hydroxy-2-pyridone of the formula and theemulsion is cast to form a layer. After exposure and development withpara-dimethylaminoaniline a. blue-violet dyestufl image: is ob- Hcrystallizes.

grams of this compound are added to 1 kilo of the silver halide emulsionand'this is cast to form a layer. After exposure and development acidwith para-dimethylaminoaniline a blue dyestufl image is obtained. a

Example 5.-1 mol of p-methyl-glutaconic acid is melted together with 1mol of stearylamine and the mass is dissolved in methanol. From thesolution 1-octadecyl-4-methyl-6-hydroxy- 2-pyridone of the formula 0 Inicu-cuiin la crystallizes.

5 grams of this compound are added to 1 mol of the silver halideemulsion and this is cast to form a layer. After exposure anddevelopment with para-dimethylaminoaniline a blue-violet dyestufl'image. is obtained.

Example 6.'I'o 1 kilooffa silver halide emulsion there is added1.3-dihydroxy-isoquinoline homo-phthalimide of the formula in the'formof a sodium salt in a quantity of 5 grams and the emulsion is cast toform a layer. After exposure and development withparadimethylaminoaniline a blue dyestufl image is obtained.

Example 7.-'T0 1 kilo of the silver halide emulsion there are added 5grams of the sodium salt of 1.4-diphenyl-6-hydroxy-2-pyridone of theformula is recrystallized from methanol. 5 grams of this compound areadded to 1 kilo of a silver halide emulsion and this is cast to form alayer. After exposure development with para-dimethylaminoanilineproduces a blue dyestufi image.

then cast to form'a layer.

Example 9.The 1 (4 aminodiphenylY- 4 methylr-6-hydroxy-2-pyridone madeas described in Example 8 is dissolved in dilute caustic soda lye and tothe solution benzoyl chloride is added by drops. 1 (4'benzoylaminodiphenyl) 4 methyl-6-hydroxy-2-pyridone of the formula isprecipitated. It is filtered with suction and washed. 5 grams of thiscompound are added to 1 kilo'of the silver halide emulsion and this iscast to form a layer. After exposure and development withpara-dimethylaminoaniline a blue dyestufl' image is obtained.

Example 10.--To 1 kilo of a silver halide emulsion there are added 5grams of 1-butyl-4- methy1-6-hydroxy-2-pyridone. The emulsion is thencast to form a layer. After exposure development with paradimethylaminoaniline yields a blue dyestufl' image.

Example 11.'To 1 kilo of a silver halide emulsion there are added 5grams of 1-hexyl-4- methyl-6-hydroxy-2-pyridone. The emulsion is thencast to form a layer. After exposure development wit h paradimethylaminoaniline yields a blue dyestuii' image.

Example 12.To 1 kilo of a silver halide emulsion there are added 5 gramsof 1-octyi-4- methyl-fi-hydroxy-Z-pyridone. The emulsion is Afterexposure development with para-dimethylaminoaniline yields a bluedyestui! image.

Example 13.To 1 kilo of a silver halide emulsion there are added 5 gramsof 1-dodecyi-4- methyl-6-hydroxy-2-pyridone. The emulsion is then castto form a layer. After exposure development withpara-dimethylaminoaniline yields a blue dyestufl image. A

Example 14.-To 1 kilo of a silver halide emulsion there are added 5grams of l -cyclohexyl-dmethyl-6-hydroxy-2-pyridone. The emulsion isthen cast to form a layer, After exposure development withpara-dimethylaminoaniline yields a blue dyestufl image.

Example 15.To 1 kilo of a silver halide emulsion there are added 5 gramsof 1-methyl-4- 'phenyl-6-hydroxy-2-pyridone. The emulsion is then castto form a layer. After exposure development with para-.dimethylaminoaniline phenyl-6-hydroxy-2-pyridone.

phenyl-6-hydroxy-2-pyridone.

yields a blue dyestuii image.

Example 16.--To 1 kilo or a silver halide emulsion there are added 5grams of 1-butyl-4- phenyl-G-hydroxy-Z-pyridone. The emulsion is thencast to form 'a layer. After exposure development withpara-dimethylaminoaniline yields a blue dyestufi image.

Example 17.To 1 kilo of a silver halide mulsion there are added 5 gramsof 1-hexyl-4- The emulsion is then cast to form a layer. After exposuredevelopment with para-dimethylaminoaniline yields a blue dyestufl image.

Example 18.To 1 kilo of a silver halide emulsion there are added 5 gramsof 1-octyl-4- phenyl-G-hydroxy-Z-pyridone. The emulsion is then cast toform a layer. After exposure development with para-dimethylamino'anilineyields a blue dyestufi image.

Example 19.To 1 kilo ofa silver halide emulsion there are added 5 gramsof l-dodecyli- The emulsion is then cast to 'form a layer.

CaHl

(EeHaCOOH The emulsion is then cast to form a layer. After exposuredevelopment with para dimethylaminoaniline yields a blue dyestuif imageExample 22.'I"o 1 kilo of a silver halide emulsion there are added 5grams of 1.4-dihydroxy- 3-carbethoxy-isoquinoline corresponding with thefollowing formula LCOOCiHi The emulsion is then cast to form a layer.After exposure development with para dimethylaminoaniline yields a bluedyestufi image.

I claim:

1. In a process of producing photographic color pictures by dyestufiforming development, the

improvement which comprises developing the exposed photographic silverhalid emulsion with an aromatic amino developer containing as thedyestufi former a compound selected from the class consisting ofhydroxypyridines and hydroxy-2- pyridones in which the N-atom istertiary.

2. In a process of producing photographic color pictures by dyestuffforming developing, the improvement which comprises exposing aphotographic silver halide emulsion containing as the dyestufi former acompound selected from the class consisting of hydroxypyridines andhydroxy-2-pyridones in which the ring N-atom is tertiary and developingsaid emulsion with an aromatic amino developer.

3. In a process of producing photographic color pictures by dyestufiforming development, the improvement which comprises exposing aphotographic silver halide emulsion containing as the dyestuif former acompound selected from the class consisting of hydroxypyridines andhydroxy-2-pyridones in which the ring N-atom is tertiary, said compoundcontaining a radicle imparting thereto fastness to diffusion withrespect to the binding agent of said emulsion, and developing saidemulsion with an aromatic amino developer;

4. Silver halide emulsion for color photography containing as a colorforming component a compound selected irom the class consisting of hydroxypyridines and hydroxy-Z-pyridones in which the ring N-atom istertiary, said compound containing a radicle imparting thereto fastnessto difiusion with respect to the binding agent of said emulsion.

5. A dyestufi forming developer comprising an aqueous olution containingan aromatic amino developing agent and a compound selected from theclass consisting of hydrorypyridines and hydroxy-2-pyridones in whichthe ring N-atom is tertiary.

6. Silver halide emulsions for color photography containing as a colorforming component a compound selected from the class consisting ofhydroxypyridines and hydroxy-2epyridones in which the ring N-atoms istertiary.

7. The silver halide emulsion defined in claim 4, wherein the radicleimparting fastness to diffusion is a long aliphatic chain.

8. The silver halide emulsion defined in claim 4, wherein the radicleimparting fastness to diffusion is linked to the compound by a linkageselected from the class consisting of an acid amide linkage, .a directnuclear carbon to carbon linkage and a direct nuclear nitrogen to carbonlinkage.

9. In the process of producing photographic colored pictures by dyestutfforming development, the improvement which comprises developing anexposed photographic silver halide emulsion with an aromatic aminodeveloper in the presence of a color former selected from the classconsisting of hydroxypyridlnes and hydroxy-2-pyridones in which the ringN-atom is tertiary.

10. The process as defined in claim 9 wherein said ring N-atom issubstituted by a substituent selected from the class consisting ofalkyl, cyclohexyl, a phenyl, and a diphenyl radical.

11. The process as. defined in claim 2 in which said ring N-atom issubstituted by a substituent selected from the class consisting of,alkyl, cyclohexyl, a phenyl and a diphenyl radical.

12. The composition as defined in claim 6 wherein said ring N-atom issubstituted by a substituent selected from the class consisting ofalkyl, cyclohexyl, a phenyl and a diphenyl radical.

13. The composition as defined in claim 4 wherein said ring N-atom issubstituted by a substituent selected from the class consisting ofalkyl, cyclohexyl, a phenyl and a diphenyl radical.

l4. The process as defined in claim 9 wherein said ring N-atom issubstituted by an alkyl radical containing up to eighteen carbon atoms.

15. The composition as defined in claim 4 wherein said ring N-atom issubstituted by an alkyl radical containing up to eighteen carbon atoms.

16. The process as defined in claim 9 wherein the color former isl-octadecyl-4-methyl-6-hydroxy-2-pyridone.

17. The process as defined in claim 10 wherein said color former is1-(4'-amino-diphenyl) -4- methyl-6-hydroxy-2-pyridone.

18. The process as defined in claim 9 wherein said color former is1-octyl-4-methyl-6-hydroxy- 2-pyridone. v

19. The composition as defined in claim' 4 wherein said color former isl-octadecyl-4- methyl-6-hydroiry-2-pyridone.

20. The composition as defined in claim 4 wherein said color former is1-(4'-amino-diphenyl) -4-methyl-6-hydroxy-2-pyridone.

21. The composition as defined in claim 4 wherein said color former isl-octyl-4-methyl-6- hydroxy-Z-pyridone.

- HERMANN LOHAUS.

cERTIncAmE OF comcnox.

atom; no. 2,295,0ohi Ailgust 11, 1942.

mznrmm Lomws;

ishoiroby certiiiod. thgt error appears in the printed'apecificncion 'ofthe above mmbor'ed' patent requiring correction as follows: Page 5 firstcolumn, line.h8, claim 1, before "IQ-atom inuert "ringand second coixmn, line 13, fbnatoma" read --atomlirie 60, for "clgim 10"-read--'-c1aini 9--; and that up and Letteraiateht should be read with maooprootioxi therein thin: the same may conform to the record of the'caste" in the Patent Office.

' Signed and sealed an; 9th day or March, A. D. 1915.

v Henry Van Aradale, (Belly Acting Commissioner of Patents.

